From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Dingwall Subject: Re: [james-xen@dingwall.me.uk: [Xen-users] Xen 4.2.0 - CPU Frequency Scaling] Date: Mon, 01 Oct 2012 21:27:14 +0100 Message-ID: <3d2b4499921255b00c1844a133efeb93@imap.dingwall.me.uk> References: <20120930161345.GA31109@dingwall.me.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Konrad Rzeszutek Wilk Cc: xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On 2012-10-01 17:33, Konrad Rzeszutek Wilk wrote: > On Sun, Sep 30, 2012 at 12:13 PM, James Dingwall > wrote: >> Hi, >> >> I didn't get any response on xen-users for this issue but so I'm >> hoping >> -devel can help. > > Lets see if we can help you. Thank you:) >> I have had problems using cpu frequency scaling since the >> xen-acpi-processor code was added to the mainline kernel source. I >> wasn't sure if the problem I was seeing was related to the old >> version >> (4.1.2) of Xen that I was using but now I'm on 4.2.0 and it still >> exists >> I thought I would check if I have a misconfiguration or if I have >> discovered a problem. My system is a dual AMD Opteron(tm) Processor >> 2423 HE on kernel 3.4.8. >> >> The xen command line is: >> console=vga,com2 com2=115200,8n1 dom0_mem=max:2048M >> dom0_max_vcpus=2 >> dom0_vcpus_pin > > Do you nee the dom0_max_vcpus=2? If they are not present does the > problem persist? >> >> The CPU scaling information reported by xenpm is below. The problem >> is that only cpuid 1 can be managed separately, all the others are > > What exactly are you trying to manage? As in what are you doing? What I was trying to achieve was 2 vcpus assigned and pinned to dom0 with the remaining available for domUs. I wanted to set the scaling governor as performance for the dom0 vcpus and ondemand for domUs. It was an obvious test to change dom0_max_vcpus and I should have done it before. On removing the parameter so that all cpus were seen in dom0 I could control the power state of them all independently. Reinstating the parameter with value of n showed that cpu 1 - (n-1) could be controlled independently while cpus 0 and n-11 were grouped together. >> bundled together and cannot be handled independently which used to >> be >> possible with the old xen kernel. If further information would be >> useful please let me know. I did have a look at xen-acpi-processor.c but it is a bit beyond me and perhaps not even the right place to start. Thanks, James